Filter and method

ABSTRACT

A fluted filter element may include one or more bridging elements to provide resistance to telescoping of the layers of the fluted filter element. The bridging elements are attached to one or both of the filter faces via adhesives, and/or mechanical means, and may also take the form of one or more beads of adhesive applied across one or both ends of the filter element. The adhesive beads may include a flexible element, such as a string, or strip of material embedded in the adhesive bead.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 11/624,921, filed on Jan. 19, 2007, which is incorporated byreference in its entirety herein. U.S. patent application Ser. No.11/624,921 This application claims the benefit of U.S. ProvisionalPatent Application No. 60/761,203, filed Jan. 23, 2006, which isincorporated by reference in its entirety herein.

FIELD OF THE INVENTION

This invention relates to fluid filters, and more particularly to theconstruction and use of filter elements having alternating layers of aface sheet material and a corrugated filter material, with thealternating layers forming substantially longitudinally oriented flutesfor passage of a fluid to be filtered.

BACKGROUND OF THE INVENTION

Filter apparatuses of the type used for filtering particulate matterfrom fluid sometimes include a filter housing having an inlet forreceiving the fluid with entrained particulate matter, and an outlet fordelivering filtered fluid to a device needing fluid that is free ofparticulate matter. For example, a filter may be provided at the airinlet of an engine or an air compressor to remove dust, water, or otherparticulate matter that could cause damage to the engine or compressorif it were not removed from the air entering the engine or compressor.

In such filters, the bulk of the particulate matter is typically removedby a filter element that is installed within the filter housing in sucha manner that the fluid must flow through the filter element, intraveling from the inlet to the outlet of the filter. The filter elementtypically includes a filter pack of porous filter material, whichremoves particulate matter from the fluid. Over time, the filter pack ofthe filter element becomes plugged or coated with particulate matter,necessitating removal and replacement of the filter element, in orderfor the filter element to continue in its function of supplyingparticulate-free fluid at the outlet of the filter.

A seal arrangement is provided at a juncture of the filter element inthe housing, so that the fluid to be filtered cannot bypass the filterelement while passing through the filter. Specifically, in one commonlyutilized prior approach to providing a fluid filter, the filter elementincludes a media pack, a mounting flange attached to the inlet end ofthe media pack, and a seal support frame, which includes an annularaxial extension thereof that projects axially from the outlet end of themedia pack for supporting a seal. The seal is configured to sealradially and/or axially against the inner surface of the housing.

The seal support frame, of such prior filter apparatuses, typicallyincludes integral webs extending completely across the outlet end of themedia pack. These webs are sometimes provided for the purpose ofresisting pressure forces acting on the media pack, which could causethe center of the media pack to bow outward in a downstream direction.It is heretofore been believed, by those having skill in the art, thatsuch seal support frames having integral webs extending completelyacross the outlet face of the media pack were particularly necessary inmedia packs formed by stacking or coiling layers of corrugated filtermaterial for a so-called “fluted filter,” in order to prevent the centerof the filter media pack from telescoping in a downward direction undermaximum rated inlet fluid pressure, particularly where the media pack issaturated with dirt or moisture. U.S. Pat. Nos. 6,190,432 and 6,610,117to Gieseke, et al. disclose filter packs having seals attached toaxially extending annular portions of a seal support frame whichincludes integral webs extending completely across the face of a mediapack.

Having the seal mounted on an axially extending annular extension of aseal support frame, as has been done in the past, together with thespace occupied by the webs at the outlet end of the filter pack,undesirably consume a significant portion of the volume inside of thehousing, and in some instances cause the housing to be larger than itwould have to be if the webbed, axially extending, seal support framecould be eliminated.

It is desirable, therefore, to provide an improved filter element, andfilter apparatus in a form which better utilizes the volume inside ofthe cavity of the filter housing, while still providing means forprecluding telescoping of the filter element.

BRIEF SUMMARY OF THE INVENTION

The invention provides an improved filter element and filter apparatus,through use of a filter element having alternating layers of a facesheet material and a corrugated filter material, with the alternatinglayers forming substantially longitudinally oriented flutes that extendaxially from a first end to a second end of the filter element, with thefilter element further having one or more bridging elements attacheddirectly to either or both of the first and second end of the filterelement and joining adjacent layers of the filter element together. Thebridging element provides resistance to telescoping of the layers of thefilter element when the filter element is subjected to operatingpressure differentials.

The bridging elements are attached to one or both of the filter facesvia adhesives, and/or mechanical means.

In one form of the invention, one or more beads of adhesive are appliedacross one or both ends of the filter element. The adhesive may be anyappropriate adhesive for use in the operating environment, including,for example, hot melt adhesives, or single or multiple part urethanes orepoxy.

In some forms of the invention, a bridging element may include aflexible element, such as a string, or strip of material embedded in anadhesive bead. The strip of material may take a variety of appropriateforms, including an amorphous, multiple parallel or twisted strands.Multiple separate strings or flexible elements may also be embedded in acommon adhesive bead.

In other forms of the invention, the bridging element includes a rigidsupporting part attached directly to one or both ends of the filterelement. The rigid supporting part may be held in place by beads ofadhesive applied beneath, or encapsulating the rigid supporting part.The rigid supporting part may include features such as outwardlyextending posts, tabs, barbs, or other appropriate mechanical featuresfor retaining the rigid supporting part on one of the ends of the filterelement. For example, a rigid supporting part may take the form of amolded plastic cross, or web-like structure attached to an end of thefilter element by beads of adhesive. Mechanical attachment features,such as barbed posts, may also be used for attaching the rigidsupporting part to an end of the filter element. In embodiments of theinvention utilizing a rigid supporting part with mechanical attachmentfeatures, the rigid supporting part may also be attached to an end ofthe filter element by an adhesive, in addition to the mechanicalattachment features.

The invention may also take the form of a method for improvingresistance of a fluted filter element to telescoping, through attachmentof a bridging element, according to the invention, to one or both endsof the filter element.

Other aspects, objectives, and advantages of the invention will beapparent from the following detailed description and the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective illustration of an exemplary embodiment of afilter element, according the invention, including a bridging elementextending across one of the end faces of the filter element.

FIG. 2 is a perspective, schematic, illustration of the manner offorming a fluted filter medium according to the invention.

FIGS. 3 and 4 are perspective illustrations showing other embodiments ofa filter element, according to the invention, including a bridgingelement having a rigid part extending across the face of the filterelement.

FIGS. 5A-5E are detailed illustrations of mechanical attachmentsextending from a rigid part, of a bridging element according to theinvention, for rigid parts of the type shown in FIGS. 3 and 4.

FIG. 6 shows an exemplary embodiment of a filter apparatus, according tothe invention, including a filter element having a bridging elementattached to one end thereof.

While the invention will be described in connection with certainembodiments, there is no intent to limit it to those embodiments. On thecontrary, the intent is to cover all alternatives, modifications andequivalents as included within the spirit and scope of the invention asdefined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a first exemplary embodiment of the invention in the formof a filter element 10 having a media pack 12. Referring to FIG. 2, themedia pack is formed from a coil of alternating face sheets 14 andcorrugated sheets 16 joined together to form a coil 18 of fluted filtermaterial.

As shown in FIG. 1, the media pack 12 is wound around a longitudinalaxis 20, with the media pack 12 extending from a first end 22 to asecond end 24 of the filter element 10. It is noted that although thefirst and second ends 22, 24 of the filter element 10 of the exemplaryembodiment are substantially flat and axially facing, in otherembodiments of the invention, one or both of the first and second ends22, 24 of the filter element 10 may take some other shape, such asrounded, spherical, conical, undulating, or other shapes appropriate tothe design of the particular embodiment of the invention.

As shown in FIG. 1, the exemplary embodiment of the filter element 10further includes a bridging element 26 having four beads of adhesive 28extending across the first end 22 of the filter element 10, and joiningadjacent layers of the media pack 12 together across the first end 22 ofthe filter element 10. In the exemplary embodiment shown in FIG. 1, thebridging element further includes strands of string 30 embedded in thebeads of adhesive 28. In other embodiments of the invention, it may bedesirable and appropriate to utilize the beads of adhesive 28 withoutthe embedded strings 30.

It is noted, that although the exemplary embodiment of the filterelement 10 shown in FIG. 1 includes a bridging element 26 attached toonly the first end 22 of the filter element, in other embodiments of theinvention a bridging element, according to the invention, may beattached to either or both of the first and second ends 22, 24 of thefilter element 10.

As shown in FIGS. 3 and 4, in other embodiments of the invention,bridging elements 32, 34 may included a rigid part 36, 38 attacheddirectly to one or both of the first and second ends 22, 24 of thefilter element 10. The rigid part may include straight legs extendingacross the end of the filter element, as shown in the rigid part 36 ofFIG. 3, and in other embodiments of the invention, a rigid part 38, asshown in FIG. 4, may include legs which are curved. In other embodimentsof the invention, rigid parts, according to the invention, may include acombination of straight or curved legs, or other shapes having portionsthereof extending at least partially across an end 22, 24 of the filterelement 10 to bridge and join together adjacent layers of the media pack12.

In some embodiments of the invention, a bridging element, having a rigidpart, such as those shown in FIGS. 3 and 4, may be joined to an end ofthe filter element 10 by an adhesive. The adhesive may be appliedcontinuously or intermittently to a facing surface of the rigid partand/or the end of the filter element 10, or in some embodiments, mayencapsulate all or portions of the rigid part 34, 36.

As shown in FIGS. 5A-5E, a rigid part 40 may also include a mechanicalattachment 42 projecting from the remainder of the rigid part 40 forengaging open ends of the flutes at one of the first or second ends 22,24 of the filter element. Such mechanical attachments 42 may be utilizedwith or without beads of adhesive in various embodiments of theinvention. Preferably, however, such mechanical attachments 42 wouldgenerally be used in conjunction with either continuous or intermittentbeads of adhesive in the same manner as described above in regard to thedescription of the embodiment shown in FIGS. 3 and 4.

As will be understood, by those having skill in the art, the mechanicalattachments 42 may take any appropriate form, such as the right circularcylindrical shaped posts shown in FIGS. 5A and 5B, the rectangularcross-shaped tabs 42 shown in FIGS. 5C and 5D, and may further includebarbs 44, as shown in FIG. 5E.

FIG. 6 shows an exemplary embodiment of a filter apparatus 46, accordingto the invention which includes a filter element 10, as described above,inserted into a filter housing 48, and sealed thereto by a seal member50 which seals the juncture of the filter element 10 and the housing 48.By the use of a bridging element 26, according to the invention, afilter apparatus 46 is provided with a filter element 10 which isresistant to telescoping of the adjoining layers of the filter mediapack 12 under pressure from the fluid flowing through the filterapparatus 46. The bridging element 26 avoids the unnecessary complexityand wastage of space within the housing 48 attendant to use of the sealsupport members having integral webs extending across the face of thefilter element in filter apparatuses prior to the invention.

The invention may be practiced in the form of a method for providingadditional resistance to telescoping of a filter element, and/or amethod for constructing a filter element having improved resistance totelescoping.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) is to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventor(s) for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventor(s) expect skilled artisans to employ such variations asappropriate, and the inventor(s) intend for the invention to bepracticed otherwise than as specifically described herein. Accordingly,this invention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

1. A fluid filter element comprising: a plurality of adjacent layersincluding a filter material and having an end face, the plurality ofadjacent layers are arranged in a coil such that the plurality ofadjacent layers are concentrically disposed; and a bridging elementcoupled to the plurality of adjacent layers across the end face to jointhe plurality of adjacent layers and resist movement of the plurality ofadjacent layers relative to one another, the bridging element includes astrip of material, the strip of material is coupled to the end face withan adhesive, the end face having a center portion and an outer edge, thestrip of material extends from the center portion to the outer edge. 2.The filter element of claim 1 wherein the strip of material is rigid. 3.The filter element of claim 1 wherein strip of material is substantiallystraight.
 4. The filter element of claim 1 wherein the strip of materialis substantially curved.
 5. The filter element of claim 1 wherein theplurality of adjacent layers include a sheet material and a corrugatedmaterial.
 6. The filter element of claim 5 wherein the plurality ofadjacent layers alternate between the sheet material and the corrugatedmaterial.
 7. The filter element of claim 1 in combination with a filterhousing.
 8. A fluid filter element comprising: a plurality of adjacentlayers including a filter material and having an end face, the pluralityof adjacent layers form substantially longitudinally oriented flutesthat extend axially from a first end to a second end of the filterelement; and a bridging element coupled to the plurality of adjacentlayers across the end face to join the plurality of adjacent layers andresist movement of the plurality of adjacent layers relative to oneanother, the bridging element includes a strip of material, the strip ofmaterial is coupled to the end face with an adhesive, the end facehaving a center portion and an outer edge, the strip of material extendsfrom the center portion to the outer edge.
 9. The filter element ofclaim 8 wherein the strip of material is rigid.
 10. The filter elementof claim 8 wherein strip of material is substantially straight.
 11. Thefilter element of claim 8 wherein the strip of material is substantiallycurved.
 12. The filter element of claim 8 wherein the plurality ofadjacent layers include a sheet material and a corrugated material. 13.The filter element of claim 12 wherein the plurality of adjacent layersalternate between the sheet material and the corrugated material. 14.The filter element of claim 8 in combination with a filter housing. 15.A method for improving resistance of a fluid filter element totelescoping, the method comprising: providing a filter element material;arranging the filter element material such that the filter elementmaterial comprises a plurality of adjacent layers, the plurality ofadjacent layers are arranged in a coil such that the plurality ofadjacent layers are concentrically disposed; providing a bridgingelement; and coupling the bridging element to an end face of the filterelement such that the bridging element joins adjacent ones of theplurality of layers to resist movement of adjacent layers relative toone another, the bridging element includes a strip of material, thestrip of material is coupled to the end face with an adhesive, the endface having a center portion and an outer edge, the strip of materialextends from the center portion to the outer edge.
 16. The method ofclaim 15 wherein the strip of material is rigid.
 17. The method of claim15 wherein strip of material is substantially straight.
 18. The methodof claim 15 wherein the strip of material is substantially curved. 19.The method of claim 15 wherein the plurality of adjacent layers includea sheet material and a corrugated material.
 20. The method of claim 19wherein the plurality of adjacent layers alternate between the sheetmaterial and the corrugated material.
 21. The method of claim 15 incombination with providing a filter housing.
 22. A method for improvingresistance of a fluid filter element to telescoping, the methodcomprising: providing a filter element material; arranging the filterelement material such that the filter element material comprises aplurality of adjacent layers, the plurality of adjacent layers formsubstantially longitudinally oriented flutes that extend axially from afirst end to a second end of the filter element; providing a bridgingelement; and coupling the bridging element to an end face of the filterelement such that the bridging element joins adjacent ones of theplurality of layers to resist movement of adjacent layers relative toone another, the bridging element includes a strip of material, thestrip of material is coupled to the end face with an adhesive, the endface having a center portion and an outer edge, the strip of materialextends from the center portion to the outer edge.
 23. The method ofclaim 22 wherein the strip of material is rigid.
 24. The method of claim22 wherein strip of material is substantially straight.
 25. The methodof claim 22 wherein the strip of material is substantially curved. 26.The method of claim 22 wherein the plurality of adjacent layers includea sheet material and a corrugated material.
 27. The method of claim 26wherein the plurality of adjacent layers alternate between the sheetmaterial and the corrugated material.
 28. The method of claim 22 incombination with providing a filter housing.